SPOKANE, Wash. - An animal researcher in Spokane, Washington is gaining world-wide attention for what may be a breakthrough in understanding canine communication.

Scientists and animal behaviorists say they are stunned by an audio recording that convincingly shows that dogs make a specific kind of sound, a type of laughter, when they are happily playing together.

What's more, when that sound is played over speakers in a kennel full of barking dogs, the dogs go silent within a minute and then seem completely at peace.

The ground-breaking research was headed by Patricia Simonet, an animal behaviorist who began the study four years ago at the Sierra-Nevada College and continued it at the Spokane County Regional Animal Protection Service, or SCRAPS program, in Spokane, Washington.

The director of the SCRAPS program says she was stunned by the experiment when it was demonstrated for her.

Simonet says she was told by dog owners that they believed their pets laughed, and now she says it looks like the science backs them up.

The 'doggie laugh' sound is similar to panting, but tests show it is indeed different, and the effect it has on other dogs in unmistakable.

At a kennel full of dogs, a television reporter armed with a sound level meter walks the hallway between two long rows of occupied dog pens.

Normally, the din of baying hounds would make it necessary to shout for a conversation, but after the laugh track is played and the dogs quietly respond, he speaks in a regular voice, and the sound meter hovers near zero.

Simonet says the audio also calms the dogs and greatly reduces their tendency to wet and defecate in their pens.

Video of the dogs shot while the sound is playing showed dogs of all different breeds sitting passively in their pens.

Simonet is now in high demand across the country after a persuasive demonstration of the research in front of 500 colleagues.

And the capper: Simonet says that even when she imitates the doggie laugh, dogs respond by willingly following her into kennels.